Rebecca Oldham found herself suffering painful cramps, and after multiple tests, New Zealand doctors decided to remove her ovaries in November, believing them to be the cause of the problem.

But then they woke the 25-year-old up to deliver some very surprising news: Instead of removing her ovaries, they were about to perform an emergency caesarean section ...

to deliver a 9-pound baby boy, with whom she was 32 weeks pregnant. "I was facing not being able to have any more children because they thought there were problems with my ovaries and all of a sudden we had a son," Oldham told the New Zealand Herald.

She and her partner already had a 20-month-old daughter, Hayley, at the time surprise son James was born. "When he cried at night I would say, 'ssshhhh Hayley,' and then remember it wasn't her and that I had a newborn baby," Oldham said.

"People say 'how could you not know?' But I really didn't." Doctors are baffled as to how the advanced pregnancy didn't show up on any tests (the following were reportedly completed: three scans, two blood tests, and six pregnancy tests), though they told her the cramps were likely caused by the baby being so snugly lodged along her back.

Oldham says she's about to receive findings of the hospital's investigation and says she hopes it will provide some answers. How often does a woman make it so late into pregnancy without knowing she's pregnant? Per Jezebel, estimates range from 1 in 500 pregnancies to 1 in 7,000.

(Click for the story of another surprise pregnancy.)

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